The civilian staff, who include 999 call handlers, scene of crime officers, police community support officers and custody officers, will be walking out from 7am following a breakdown in talks.

The workers who have borne the brunt of the coalition’s police cuts have seen their pay plummet by 13% cent in real terms since 2010. They are pushing for a 3 per cent pay rise, or £500, whichever is the greater.

Unite national officer Fiona Farmer said: “Plummeting pay levels have led to police staff increasingly struggling to pay the bills and put food on the table.

“They have been on the sharp end of the coalition’s police cuts struggling to do their job in the face of a 13% pay cut in real terms.

“The 1% being offered does nothing to halt the decline in pay. We had hoped that we could reach a settlement, but a failure by the employers to address pitiful pay levels has left our members with the last resort of strike action.

“We hope we can still avoid the disruption that strike action will bring and reach a negotiated settlement that begins to halt plummeting pay levels.”